The present invention relates to an apparatus for inflating a vehicle occupant protection device. The present invention particularly relates to a hybrid inflator.
A hybrid inflator for inflating a vehicle occupant protection device includes a quantity of a stored gas and a body of combustible material. The body of combustible material typically comprises a binder which is mixed with the other components of the body of combustible material to help form a moldable or extrudable mass. An igniter is actuatable to ignite the body of combustible material. As the body of combustible material burns, combustion products heat the stored gas. This increases the pressure of the stored gas. The heated stored gas and the combustion products form an inflation fluid for inflating the vehicle occupant protection device.
If the ambient temperature surrounding the inflator becomes too high, the binder, and thus the body of combustible material could deform. Deformation of the body of combustible material could reduce the reliability of ignition and the output production of the body of combustible material. Accordingly, it is desirable to provide a body of combustible material which can resist deformation and can ignite and combust reliably after withstanding exposure to relatively high temperatures for extended periods of time.
The present invention relates to an apparatus for use in inflating a vehicle occupant protection device. The apparatus comprises a container and a combustible material stored in the container. The combustible material comprises a binder selected from the group consisting of cellulose acetate butyrate and cellulose acetate propionate. The binder has a melting point in the range of about 230xc2x0 C. to about 260xc2x0 C. Igniter means is provided for igniting the combustible material. The combustible material, when ignited, burns and generates combustion products. A conduit directs the combustion products toward the vehicle occupant protection device.